Condom doubts!

Anne
How do you know that your condom broke?
The 1st time I had sex with my bf I saw the sperm there, and the second time I heard a noise (it could be the air idk) but after having sex I filled it with water and nothing came out so it's impossible for the condom to have broken right?
I also had anal without a condom but he didn't cum inside me. He did it far always form my vagina so it's really impossible for me to be pregnant right?